<template>
    <div class="detail-header">
        <router-link
        tag="div"
        to="/"
        class="header-abs"
        v-show="showAbs">
          <div class="iconfont header-abs-back">&#xe624;</div>
        </router-link>
        <div class="header-fixed"
        v-show="!showAbs"
        v-bind:style="opacityStyle">
            <router-link
            to="/" >
              <div class="iconfont header-fixed-back">
                &#xe624;</div>
            </router-link>
          景点详情
        </div>
    </div>
</template>

<script>
export default {
  name: 'DetailHeader',
  data () {
    return {
      showAbs: true,
      opacityStyle: {
        opacity: 0
      }
    }
  },
  methods: {
    handleScroll () {
      const top = document.documentElement.scrollTop
      if (top > 60) {
        let opacity = top / 140
        opacity = opacity > 1 ? 1 : opacity
        this.opacityStyle = {
          opacity
        }
        this.showAbs = false
      } else {
        this.showAbs = true
      }
      // console.log(document.documentElement.scrollTop)
    }
  },
  activated () {
    window.addEventListener('scroll', this.handleScroll)
  },
  deactivated () {
    window.removeEventListener('scroll', this.handleScroll)
  }

}
</script>

<style lang="stylus" scoped>
   @import '~styles/varibles.styl'
  .header-abs
    position absolute
    left .2rem
    top 1.5rem
    // bottom .8rem
    width .8rem
    height .8rem
    line-height .8rem
    border-radius .4rem
    text-align center
    background rgba(0, 0, 0, .8)
    .header-abs-back
      color #fff
      font-size .4rem
  .header-fixed
    z-index 3
    position: fixed
    top 0
    left 0
    right 0
    // overflow: hidden
    height: $headerHeihgt
    line-height: $headerHeihgt
    text-align: center
    color: #fff
    background: $bgColor
    font-size: .32rem
    .header-fixed-back
      position: absolute
      top: 0
      left: 0
      width: .64rem
      text-align: center
      font-size: .4rem
      color: #fff
</style>
